Thursday, June 16, 2016

Why doing a D&C after a miscarriage is a bad idea

One of the hardest things for an infertile couples to deal with is a miscarriage after an IVF cycle . While not getting pregnant can be heartbreaking , losing a pregnancy after getting pregnant is far worse . Sadly, IVF does not provide any protection against miscarriage , and just like a natural pregnancy has a miscarriage rate of about 10% , so does an IVF pregnancy . The loss is far more acute, because this is such a deeply desired pregnancy . A miscarriage can often be the last straw which breaks the camel' s back , and many patients will give up after this. This is a shame, because the fact that you have got pregnant ( even if you did miscarry) means your chances of having a healthy baby have actually improved !

Most pregnancy losses ( whether after IVF or after sex in the bedroom) occur in the first trimester - usually in the first 8 weeks. They are called missed abortions - perhaps because the embryo is missing on the ultrasound scan . The HCG levels rise as expected, but when the doctor does the scan at 6 weeks, this shows that there is a pregnancy sac. but it's empty - there is no baby.

Patients can't understand how they can be pregnant without there being a baby. The reason is that pregnancy consists of both the embryo , as well as the placenta - the extra embryonic tissue which is needed to support the pregnancy. It's the placenta which produces the HCG, which is why the HCH levels rise well, even though there is no embryo ( the medical term for which is anembryonic pregnancy).

The commonest for an early miscarriage is a genetic problem in the baby , and this is why many doctors advise patients to do a D&C ( dilatation and curettage) after a missed abortion , so that they can send the pregnancy tissue (called the products of conception ) for chromosomal testing , in order to document this. This seems quite logical at first blush, but is actually a completely pointless test , especially if this is your first miscarriage. This is because the test result does not change your treatment options for the future at all.

Let me explain . Just because the karyotype report is normal, this does not mean that the reason for the miscarriage is not a genetic problem . Remember that all a karyotype can do is to count the number of chromosomes and check their shape - it cannot test for all possible lethal genetic defects, because it's such a crude genetic test. Also, even if the karyotype is abnormal, this makes precious little difference for the future, because most chromosomal anomalies are because of random defects, and are very unlikely to recur in the next pregnancy.

Just because there is a chromosomal error in this pregnancy, this doesn't mean that the patient is at increased risk for a chromosomal defect the next time she does IVF. Also, do remember that the IVF procedure itself does not increase the risk of the embryo having a genetic defect - this defect is usually completely random.

Chromosomal testing of the fetus (using either cell culture or genetic sequencing techniques) is expensive, and we don't learn anything useful from it . What's much worse is that doing a D&C can actually harm the patient's future fertility.

Often the doctor needs to do a lot of scraping in order to completely remove the fetus after a missed abortion, and this can cause intrauterine adhesions , which reduce your chances of getting pregnant in the future.

If you are unlucky and do end up having a missed abortion after your IVF treatment, you need to be emotionally resilient ; terminate the pregnancy with medical therapy ; and learn to look at the glass as being half-full. The fact that you have got pregnant means your chances of having a healthy baby are actually far better and someone who's never been pregnant at all - and if you can carry to 8 weeks, there's a very good chance you can carry to 8 months as well !